common rock-rose, long-branch frostweed
[Cistus canadensis L., more...]
Etymology: Helianthemum: from the Greek helios, "sun," and anthemon, "flower," because the flowers open only in the sun
Plants: erect, perennial, 8"-24" tall forb; stems scattered, branching when mature, the branches becoming taller than the main stem
Leaves: alternate, narrowly-oblong, tapering at the base and tip
Flowers: yellow, 5-parted, 2/3"-1 1/8" wide; inflorescence of 1-2 flowers in a branched cluster (cyme) at the top of the stem; blooms May-June, usually 2-3 weeks earlier than H. bicknellii.
Habitat: dry; prairies, woods, inland sands
Conservation Status: Native
Floristic Rating: Coefficient of Conservatism = 6 Atlas of the Wisconsin Prairie and Savanna Flora: by T.S. Cochrane & H.H. Iltis: habitat, distribution infomation / flowering and fruiting times USDA Plants Database: Federal Distribution and detailed information including photos David G. Smith's "Delaware Wilflowers": Beautiful photographs; descriptions Southwest School of Botanical Medicine: Britton & Brown Illustrated Flora - 2nd Edition (1913) "An Illustrated Flora of the Northern United States and Canada"